Note 11 - Long-term Debt - Principal Payments (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
2018	$ 42,580,323
2019	42,505,323
2020	118,038,569
2021	53,874,219
2022	58,478,532
Thereafter	71,498,875
Total	$ 386,975,841	$ 400,229,914

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-SubTopic 20
-Section 50
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-SubTopic 10
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